At present, with the gradual deepening of water injection development of oil and gas fields, separate layer water injection construction of a water injection well is becoming more frequent. The separate layer water injection means that a packer is lowered into the water injection well to separate oil reservoirs that differ greatly, and then an intelligent water distributor is used for separate layer water distribution, such that the water injection rate of a high permeability layer is controlled, while the water injection rate of medium and low permeability oil reservoirs is increased, and ultimately it is ensured that the effects of various oil reservoirs are exerted. The water injection rate, pressure, etc. of each water injection layer is hardly monitored and controlled on the ground in real time during the separate layer water injection.
In order to solve the above problems, it is possible to mount a male connector in an oil and gas well, and mount a female connector at the head of a cable. During working, the cable is lowered first to a certain depth, and then the female connector and the male connector are docked, such that ground monitoring and control equipment is electrically connected with a pressure sensor, a flow sensor and a temperature sensor on a water distributor, i.e., the collected pressure and flow information is transmitted to the ground equipment via the cable. However, the cable has a low lowering speed and low connection efficiency, and the oil and gas well is too deep to ensure accurate docking between the male connector and the female connector. The male connector and the female connector cannot be connected steadily under a water pressure during the water injection even if they are connected. Therefore, there is an urgent need for a set of device that can realize ground and downhole real-time communication, detect and control the downhole water injection rate, pressure, etc., in each layer, and ensure that the male connector and the male connector are connected firmly.